1. Field of the Invention
This invention relates to shoes designed to minimize impact shock and to increase stability and support.
2. Description of the Related Art
The athletic shoe is a combination of elements, which cooperatively interact in an effort to minimize weight and maximize comfort, cushioning, stability and durability. When running and walking, generally the foot makes initial contact with the ground at a force of 2.5 times their body weight, which may be repeated many times per minute per foot. The cushioning in most athletic shoes is supplied through the foam midsole that can be made from ethylene vinyl acetate (EVA) or polyurethane.
Shoes in the related art have included thicker midsoles to provide more cushioning ability. However, added thickness of foam in the midsole can cause the midsole to have increased stiffness in bending. Under these conditions, the lateral corner of the sole can tend to operate as a fulcrum upon heel strike and create an extended lever arm and greater moment, which can cause the foot to rotate medially and pronate with greater velocity than desired. This can lead to over-pronation of the foot and possible injury. Further, this condition can present a potentially unstable condition for the foot and result in the transmission of higher than desired levels of impact stress due to the relatively small surface area of contact.
It is an object of the present invention to provide a sole for an article of footwear that reduces or overcomes some or all of the deficiencies inherent in prior known footwear. Particular objects and advantages of the invention will be apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this field of technology, in view of the following disclosure of the invention and detailed description of certain preferred embodiments.